Battery Pack With Guide Rails For Improved Terminal Alignment

ABSTRACT

A battery pack may include a battery cell, a cradle, a board and a housing. The cradle may be coupled with the battery cell and may include one or more guide members extending from and integrally formed with a surface of the cradle. The board may be mounted to the cradle and may include a plurality of terminal contacts electrically connected with the battery cell. The one or more guide members may be adapted to guide a device into engagement with the terminal contacts. The housing may at least partially enclose the cradle and the battery cell and may include one or more guide apertures and a plurality of terminal apertures. The one or more guide members may protrude through the one or more guide apertures. Each of the terminal apertures may be aligned with a corresponding one of the plurality of contacts.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/714,801, filed on Oct. 17, 2012. The entire disclosure of the aboveapplication is incorporated herein by reference.

FIELD

The present disclosure relates to a battery pack for powering anelectric device.

BACKGROUND

Electric tools and appliances are often powered by rechargeable batterypacks to provide convenience and mobility. The battery packs can includenickel-cadmium (NiCd), nickel metal-hydride (NiMH), lead-acid and/orLithium-ion (Li-ion) battery cells, for example. These battery packs maybe coupled with the cordless devices and may power an electric motor ofthe device, for example. The battery pack may be removed from thecordless device and charged in a battery charger or charged in thecordless device itself.

Terminal assemblies can be provided on the battery pack, the cordlessdevice and the charger for releasably mechanically and electricallyconnecting the battery pack to the cordless device or charger. Due tothe frequent interconnections between the terminal blocks associatedwith connecting and disconnecting the battery pack from the cordlessdevice and the charger, any misalignment between mating contacts on theterminal blocks may damage the terminal assemblies. This misalignmentcan adversely affect the electrical connection between the two terminalassemblies, which can render the battery pack unusable.

This section provides background information related to the presentdisclosure and is not necessarily prior art.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

In one form, the present disclosure provides a battery pack that mayinclude a battery cell, a cradle, a board and a housing. The cradle maybe coupled with the battery cell and may include one or more guidemembers extending from and integrally formed with a surface of thecradle. The board may be mounted to the cradle and may include aplurality of terminal contacts electrically connected with the batterycell. The one or more guide members may be adapted to guide a device(e.g., an electric tool or appliance, a battery charger and/or anassembly fixture) into engagement with the terminal contacts. Thehousing may at least partially enclose the cradle and the battery celland may include one or more guide apertures and a plurality of terminalapertures. The one or more guide members may protrude through the one ormore guide apertures. Each of the terminal apertures may be aligned witha corresponding one of the plurality of contacts.

In another form, the present disclosure provides a method ofmanufacturing a battery pack. The method may include providing a batterycell, a cradle and a board. The cradle may include a mounting interfaceand one or more guide members. The mounting interface may include anengagement feature. The board may include a terminal contact attachedthereto. The method may also include coupling the cradle to the batterycell and coupling the board to mounting interface of the cradle to allowrelative movement between the board and the cradle. The one or moreguide members may be engaged with one or more corresponding surfaces ofa fixture. The board may be positioned relative to the cradle byengaging a terminal member of the fixture with the terminal contact.

In yet another form, the present disclosure provides a battery pack thatmay include a plurality of battery cells, a cradle, a board and ahousing. The cradle may be coupled with the battery cells and mayinclude first and second guide members extending from and integrallyformed with a surface of the cradle. The board may be mounted to thecradle and may include a plurality of terminal contacts electricallyconnected with the battery cells. The housing may at least partiallyenclose the cradle and the battery cells and may include first andsecond guide apertures and a plurality of terminal apertures. The firstand second guide members may protrude through the first and second guideapertures, respectively. Each of the terminal apertures may be alignedwith a corresponding one of the plurality of contacts. Openings of theterminal apertures may face an end of the housing. The first and secondguide members may be disposed entirely between the openings of theterminal apertures and the end of the housing. The board may beselectively movable relative to the first and second guide members. Thecradle may include a first aperture that threadably receives a fastener.The board may include a second aperture through which the fastenerextends. The second aperture may include a larger diameter than thefirst aperture to allow adjustment of the board relative to the cradlewhen the fastener is received in the first and second apertures, butbefore a head of the fastener is tightened against the board. The firstguide member may include first and second legs and a cross-memberextending therebetween. The second guide member may include only asingle leg that is substantially parallel to the first and second legsof the first guide member. Openings of the terminal contacts may face afirst end of the cradle. The first and second guide members may bedisposed between the openings of the terminal contacts and the first endof the cradle.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of a battery pack according to theprinciples of the present disclosure;

FIG. 2 is a partial perspective view of the battery pack of FIG. 1;

FIG. 3 is a perspective view of a portion of a housing of the batterypack;

FIG. 4 is a perspective view of a cradle of the battery pack having aboard mounted thereto according to the principles of the presentdisclosure;

FIG. 5 is a perspective view of the cradle of FIG. 4; and

FIG. 6 is a plan view of the cradle and board with an alignment fixtureengaging guide members and terminal contacts of the cradle and board,respectively, according to the principles of the present disclosure.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

With reference to FIGS. 1-6, a battery pack 10 is provided that mayinclude a housing assembly 12 (FIGS. 1 and 2), a plurality of batterycells 14 (FIGS. 4 and 5), a cradle 16 (FIGS. 4-6), and a board 18 (FIGS.4 and 6). The battery pack 10 may be operatively connectable to one ormore power tools, appliances and/or other electric devices (not shown)and to a battery charger (not shown).

As shown in FIGS. 1 and 2, the housing assembly 12 may include a tophousing 20 and a bottom housing 22. The top and bottom housings 20, 22may be molded and/or otherwise formed from a polymeric material, forexample. The top and bottom housings 20, 22 may be joined together by asnap-fit, press-fit, one or more fasteners and/or any other suitablejoining method. The top and bottom housings 20, 22 may cooperate tosubstantially enclose the battery cells 14, cradle 16 and board 18.

Referring now to FIGS. 1-3, the top housing 20 may include a baseportion 24 and an upper portion 26 that slidably engage a power tool andbattery charger. The base portion 24 may include first and second ends28, 30 and first and second guide apertures 32, 34 disposed proximatethe first end 28. The upper portion 26 may extend from the base portion24 and may include first and second ends 36, 38. The first and secondguide apertures 32, 34 may be disposed between the first end 28 of thebase portion 24 and the first end 36 of the upper portion 26. The firstend 36 of the upper portion 26 may include a plurality of terminal slots40. The upper portion 26 may also include a first pair of guide rails 42and a second pair of guide rails 44. Corresponding guide rails (notshown) of the power tool and battery charger may slidably engage thefirst and second pairs of guide rails 42, 44 to attach the battery pack10 to the power tool or charger.

The second end 38 of the upper portion 26 may be generally aligned withthe second end 30 of the base portion 24 and may include an opening 46through which a latch 48 extends. The latch 48 may be a part of arelease mechanism for releasing the battery pack 10 from engagement withthe power tool or battery charger.

Referring now to FIGS. 4 and 5, the battery cells 14 may be supported bythe bottom housing 22 and the cradle 16 and may be disposedtherebetween. The battery cells 14 may include one or more of a lithiumion (Li-ion), nickel cadmium (NiCd), nickel metal hydride (NiMH) and/orlead-acid battery cells, for example, and/or any other type of batterycell. The battery cells 14 may be connected in series and/or parallel toeach other and to the board 18. It will be appreciated that the batterypack 10 could include any number of battery cells 14.

Referring now to FIGS. 4-6, the cradle 16 may be molded or otherwiseformed from a polymeric material, for example, and may include a body50, a mounting interface 52, a first guide member 54 and a second guidemember 56. The body 50, mounting interface 52 and first and second guidemembers 54, 56 may be integrally formed with each other. The body 50 mayinclude a plurality of contoured recesses 58 in which correspondingbattery cells 14 may be nested (as shown in FIG. 4). The battery cells14 could be fixed to the cradle 16 by metallic straps (not shown), snapfit, fasteners and/or any other suitable attachment device or method.The body 50 of the cradle 16 may be fixedly attached to the top and/orbottom housings 20, 22 (FIG. 1) by a snap or press fit, one or morefasteners and/or any other attachment device or method.

The mounting interface 52 may support the board 18 within the housingassembly 12 and may include a plurality of bosses 60 and one or morestops 62 (shown best in FIG. 5). The bosses 60 may extend upward fromthe body 50 toward the top housing 20 and define a first plane above thebody 50 upon which the board 18 is disposed. In some embodiments, thebosses 60 could be integrated into a single unitary feature or surface.The stops 62 may define a second plane against which the board 18 may bedisposed. The second plane may be perpendicular to the first plane. Themounting interface 52 may also include an engagement feature, which inthe particular example provided, is embodied as a boss 64 having athreaded aperture 66 (shown in FIG. 5).

The first and second guide members 54, 56 may extend upward from thebody 50 and may protrude through the first and second guide apertures32, 34, respectively, of the top housing 20 when the battery pack 10 isin a fully assembled state (as shown in FIGS. 1 and 2). The first guidemember 54 may include a first leg 68, a second leg 70 and a cross-member72. The first and second legs 68, 70 may be substantially parallel toeach other and may be connected to each other by the cross-member 72.The first leg 68 may include a planar outer side 76. The first leg 68may be longer than the second leg 70 and may include a chamfered portion74. The second leg 70 and/or the cross-member 72 may be provided torestrict or prevent the battery pack 10 from being engaged with a toolor charger that is incompatible with the battery pack 10. That is, atool or charger that is intended to operate with a battery pack of adifferent voltage, type and/or configuration may include structure thatwould interfere with the second leg 70 and/or cross-member 72 to preventengagement therewith. It will be appreciated from the present disclosurethat the first guide member 54 could include any other suitable shapeand/or configuration.

The second guide member 56 may be substantially parallel to the firstand second legs 68, 70 of the first guide member 54. The second guidemember 56 may include a planar outer side 78 and a chamfered portion 80.The planar outer side 78 of the second guide member 56 may be parallelto the planar outer side 76 of the first guide member 54. It will beappreciated from the present disclosure that the second guide member 56could include any other suitable shape and/or configuration.

The board 18 may be a printed circuit board and may be in electricalcommunication with the battery cells 14. The board 18 may include aplurality of terminal contacts 82 soldered thereon or otherwise attachedthereto. In the particular example provided, the terminal contacts 82are female tulip clips adapted to receive corresponding male bladeterminals (not shown) of the power tool and battery charger. It will beappreciated that the terminal contacts 82 could include any type of maleor female contacts. Flared openings 83 of the terminal contacts 82 mayface toward the first end 36 of the top housing 20 such that when thebattery pack 10 is in the fully assembled state (FIG. 1), the openings83 of each of the terminal contacts 82 are aligned with a correspondingone of the terminal slots 40 so that male blade terminals of the powertool and battery charger can be received through the terminal slots 40and openings 83 and engage the terminal contacts 82 when the batterypack 10 is fully engaged with the power tool or battery charger. In theparticular example provided, the entire first and second guide members54, 56 may be disposed between the terminal contacts 82 and the firstend 28 of the base portion 24 of the top housing 20.

The board 18 may also include an aperture 84 (FIG. 6) through which athreaded fastener 86 may extend to threadably engage the threadedaperture 66 in the cradle 16. The aperture 84 may include a largerdiameter than the threaded aperture 66 to enable the board 18 to movelaterally relative to the cradle 16 in a direction X and/or a directionY (shown in FIG. 6) while the fastener 86 is engaged with the apertures66, 84, but before the fastener 86 is tightened down against the board18. While the aperture 84 is shown in FIG. 6 as a circular hole, in someembodiments, the aperture 84 may include a slot that is elongated in thedirection X. A back edge 90 of the board 18 may abut the stops 62 of themounting interface 52 of the cradle 16. It will be appreciated that insome embodiments, the fastener 86 may be a self-tapping screw. In suchembodiments, the boss 64 may be initially formed without the threadedaperture 66 (or initially formed with only a pilot hole), and thefastener 86 may be driven into the boss 64.

With reference to FIGS. 1-6, a method of manufacturing the battery pack10 will be described. The cradle 16 and the top and bottom housings 20,22 may each be molded and/or otherwise formed to include the featuresdescribed above and/or shown in the figures. The board 18 may be mountedto the cradle 16 and positioned such that the terminal contacts 82 arein registration with one or both of the first and second guide members54, 56, as will be described in more detail below.

With particular reference to FIGS. 4-6, a method of mounting the board18 to the cradle 16 and positioning the board 18 relative to the cradle16 will be described in detail. First, the board 18 may be placed on thebosses 60 of the mounting interface 52 of the cradle 16. Then, the board18 may be positioned such that the aperture 84 in the board 18 isgenerally aligned with the threaded aperture 66 in the cradle 16. Thefastener 86 can be inserted through the aperture 84 in the board 18 andthreadably engaged with the threaded aperture 66 in the cradle 16.

Before the fastener 86 is fully tightened against the board 18 tofixedly secure the board 18 to the cradle 16, the position of the board18 may be adjusted in the direction X and/or in the direction Y (FIG. 6)so that the terminal contacts 82 are in registration with one or both ofthe first and second guide members 54, 56. To adjust the position of theboard 18 in the direction X, an alignment fixture 100 (shownschematically in FIG. 6 is phantom lines) may engage the first andsecond guide members 54, 56 and the terminal contacts 82. As shown inFIG. 6, the alignment fixture 100 may include first and second guidewalls 102, 104 and a plurality of blade terminals 106 disposed betweenthe guide walls 102, 104 and extending substantially parallel thereto.The first and second walls 102, 104 are positioned relative to eachother and to the blade terminals 106 in a manner that matchescorresponding guide rails and blade terminals of the power tool andbattery charger.

The first and second guide walls 102, 104 of the alignment fixture 100may be slid into engagement with the first and second guide members 54,56 until the blade terminals 106 are inserted through the flaredopenings 83 of the terminal contacts 82. Contact between the bladeterminals 106 and the openings 83 of the terminal contacts 82 may urgethe board in the direction Y until the back edge 90 of the board 18 isin abutting contact with the stops 62 of the cradle 16. Any initialmisalignment in the direction X between the openings 83 and the bladeterminals 106 can be eliminated when the blade terminals 106 arereceived into the terminal contacts 82. That is, if the openings 83 areinitially slightly misaligned with the blade terminals 106, insertion ofthe blade terminals 106 into the openings 83 of the terminal contacts 82will cause the board 18 to move in the direction X to a position thataligns the openings 83 with the blade terminals 106. Once the board 18is positioned relative to the first and second guide members 54, 56, thefastener 86 can be tightened against the board to fixedly secure theboard 18 relative to the cradle 16.

Referring again to FIGS. 1-6, the battery cells 14 may be received inthe contoured recesses 58 of the cradle 16 and, in some embodiments, maybe snap fit and/or otherwise attached to the cradle 16 in a manner thatallows the battery cells 14 to electrically communicate with theterminal contacts 82. The battery cells 14 and cradle 16 may then bereceived into the bottom housing 22. It will be appreciate that theboard 18 could be mounted to the cradle 16 and aligned relative to theguide members 54, 56 before or after the cradle 16, battery cells 14 andbottom housing 22 are attached to each other. It will be appreciatedthat, in some embodiments, the battery cells 14 could be received in thebottom housing 22 and then the cradle 16 (with or without the board 18mounted thereon) could be placed over the battery cells 14 and engagedwith the bottom housing 22.

Next, the top housing 20 is placed over the cradle 16 and board 18 suchthat the first and second guide members 54, 56 protrude through thefirst and second guide apertures 32, 34, respectively, and the terminalcontacts 82 are aligned with the terminal slots 40 (shown best in FIG.2). When the first and second guide members 54, 56 of the cradle 16 arereceived through the first and second guide apertures 32, 34 in the tophousing 20, the fit between the guide members 54, 56 and respectiveguide apertures 32, 34 ensures that the top housing 20 is positionedrelative to the cradle 16 such that the terminal slots 40 are preciselyaligned with the terminal contacts 82. The top housing 20 can then besecured to the bottom housing 22 via a snap fit, one or more fasteners,ultrasonic welding, adhesive, and/or any suitable attachment means. Insome embodiments, the cradle 16 could include one or more additionalposts or bosses (not shown) that engage one or more slots or apertures(not shown) in an underside of the top housing 20 to ensure properpositioning or alignment of the cradle 16 relative to the top housing20.

Positioning the board 18 such that the terminal contacts 82 are inregistration with the first and second guide member 54, 56, as describedabove, can prevent the terminal contacts 82 from being bent or otherwisedamaged when the battery pack 10 is engaged with the power tool or thebattery charger. That is, when the power tool or battery charger is slidinto engagement with the battery pack 10, guide rails of the power toolor battery charger may slidably engage the first and second guidemembers 54, 56 protruding through the top housing 20. This engagementwill ensure that the blade terminals of the power tool or batterycharger are properly aligned with the terminal contacts 82, so that theterminal contacts 82 and blade terminals are not bent or otherwisedamaged when the blade terminals are inserted into the terminal contacts82. Preventing such damage to the terminal contacts 82 and bladeterminals will improve the longevity and reliability of the battery pack10, the power tool and battery charger.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

1. A method of manufacturing a battery pack comprising: providing abattery cell; providing a cradle including a mounting interface and aguide member, the mounting interface including an engagement feature;providing a board having a terminal contact attached thereto; couplingthe cradle to the battery cell; coupling the board to the mountinginterface of the cradle to allow relative movement between the board andthe cradle; engaging the guide member with a surface of a fixture; andpositioning the board relative to the cradle by engaging a terminalmember of the fixture with the terminal contact.
 2. The method of claim1, fixedly securing the board to the cradle after the step ofpositioning the board relative to the cradle.
 3. The method of claim 1,wherein providing the cradle includes molding the guide member with abody of the cradle.
 4. The method of claim 1, wherein coupling thecradle to the battery cell includes nesting the battery cell in a recessin the cradle.
 5. The method of claim 1, wherein the board includes aplurality of female terminal contacts.
 6. The method of claim 1, furthercomprising providing a housing at least partially encasing the cradleand the battery cell, the first and second guide members protrudingthrough first and second apertures, respectively, of the housing.
 7. Themethod of claim 1, further comprising providing at least one of thefirst and second guide members with a structure to restrict engagementof the battery pack with an incompatible device.
 8. The method of claim1, further comprising engaging another guide member with another surfaceof the fixture.
 9. The method of claim 8, wherein one of the guidemembers includes first and second legs and a cross-member extendingtherebetween.
 10. The method of claim 9, wherein the other one of theguide members includes only a single leg that is substantially parallelto the first and second legs.
 11. The method of claim 1, whereinopenings of the terminal contacts face a first end of the cradle, andwherein the guide member is disposed between the openings of theterminal contacts and the first end of the cradle. 12.-20. (canceled)21. A method for manufacturing a battery pack, comprising: providing aboard having a plurality of terminal contacts attached thereto;providing a cradle having a top surface and a bottom surface, where thetop surface includes first and second guide members protrudingtherefrom; coupling the board to the cradle in a manner that permitssliding movement therebetween; sliding an alignment fixture intoengagement with the first and second guide members of the cradle;adjusting positioning of the board in relation to the cradle while thealignment fixture is engaged with the first and second guide members ofthe cradle; and fixedly securing the board to the cradle to form acradle assembly.
 22. The method of claim 21 further comprises providingone or more battery cells; and coupling the battery cells to the cradle,where the bottom surface of the cradle is configured to nest the one ormore battery cells.
 23. The method of claim 21 further comprisesmounting the cradle assembly into a bottom shell; joining a top shell tothe bottom shell, such that the top shell includes a first and secondguide apertures such that the first and second guide members protrudethrough the first and second guide apertures of the top shell whenjoined to the bottom shell.
 24. The method of claim 21 wherein thealignment fixture includes a plurality of alignment blades which alignwith and electrically engage with the plurality of terminal contactswhen the alignment fixture is engaged the first and second guide membersof the cradle.
 25. The method of claim 21 wherein openings of theplurality of terminal contacts face a given end of the cradle and thefirst and second guide members are disposed between the openings of theterminal contacts and the given end of the cradle.
 26. The method ofclaim 21 wherein at least one of the first and second guide membersincludes a structure to restrict engagement of the battery pack with anincompatible device.
 27. The method of claim 26 wherein one of the firstand second guide members includes first and second legs and across-member extending therebetween.
 28. The method of claim 27 whereinthe other of the first and second guide members includes only a singleleg that is substantially parallel to the first and second legs.
 29. Themethod of claim 21 wherein coupling the board to the cradle furthercomprises aligning an aperture in the board with a threaded aperture inthe cradle and inserting a fastener through the aperture in the boardand into the threaded aperture of the cradle.
 30. The method of claim 29wherein fixedly securing the board to the cradle to form a cradleassembly further comprises tightening the fastener against the board tofixedly secure the board to the cradle.